Defense Response and Suppression of Blight Disease of Pepper by Water Extract from Spent Mushroom Substrate of .

The spent mushroom substrate (SMS) of that was derived from sawdust bag cultivation was used as materials for controlling blight disease of pepper. Water extract from SMS (WESMS) of inhibited mycelial growth of , suppressed blight disease of pepper seedlings by 65% and promoted growth of the plant over 30%. In high performance liquid chromatography (HPLC) analysis, oxalic acid was detected as the main organic acid compound in WESMS and inhibited the fungal mycelium at a minimum concentration of 200 mg/l. In quantitative real-time PCR, the transcriptional expression of (PR protein 1), (β-1,3-glucanase), (PR protein 4), and (PR protein 10) were significantly enhanced on WESMS and DL-β-aminobutyric acid (BABA) treated pepper leaves. In addition, the salicylic acid content was also increased 4 to 6 folds in the WESMS and BABA treated pepper leaves compared to water treated leaf sample. These findings suggest that WESMS of suppress blight disease of pepper through multiple effects including antifungal activity, plant growth promotion, and defense gene induction.